Packaging



Dec. 29, 1942. T. F. MENZEL PACKAGING Filed May 17, 1940 2 Sheets-Sheet l 1/ 21 INVENTOR THEODORE F. MNZL E ATTORNEY Dec. 29, 1942. 'r. F. MENZEL PACKAGING Filed May 17, 1940 2 Sheets-Sheet 2 v INVENTOR 7796502025 FMENZEL 4m; B J ATTORNEY Patented Dec. 29, 1942 2,306,399 PACKAGING Theodore F.

Menzel, Long Island City, signor to Millie Patent Holding 00.,

poration of New York Application May 17, 1940, Serial No. 335,694

9 Claims.

This invention relates to the packaging art, and more particularly to the manufacture of filled containers or bags.

Although in practising the invention filled containers or bags may be made for use in packaging various soluble materials, bluing, dyes and the like, the embodiment of the invention as herein described is directed to improvements in the manufacture of packaging of tea, coffee or similar essence containing products made and sold as complete package articles as for example, socalled tea-balls or coffee balls ready for use in brewing beverages. The invention is also directed to the manufacture of novel filter sheet material and to an improved method of producing same, said sheet material being particularly adapted for making the containers or bags for said package-articles, said filter sheet material having inherent properties to permit heat sealing of closures, joints and seams to eliminate the usual mechanical fastening means such as sewing, stitching or stapling commonly used for such purposes.

Among the objects of the invention is to generally improve heat sealing filter sheet material and package articles using such sheet material, and the method of manufacturing said sheet material, the package-article having containers or bag portions thereof made with closure joints and seams formed in part or entirely by heat sealing, the improved sheet material having as an integral part thereof heat sealing properties so as to require no additional adhesive, which shall comprise few elementary parts formed by simple methods and arranged to provide an inexpensive article of new, neat and attractive appearance which shall be particularly adapted for large scale production with high speed automatic bag making, filling and sealing, and which improved method of manufacture of said sheet material, and package-article shall be efiicient and practical to ahigh degree.

Other objects of this invention will in part be obviousand in part hereinafter pointed out.

Theinvention accordingly consists in the features of constructions and method, combinations of elements, arrangements of parts and steps in the process of manufacture which will be exemplified in the constructions and method hereinafter described and of which the scope of application will be indicated in the following claims In the accompanying drawings in which is shown various possible illustrative embodimentsI of this invention;

Fig. 1 is a diagrammatic plan view illustrating 55 N. Y., as- Inc., a colthe process for manufacturing heat sealing filter sheet material embodying the invention;

Figs. 2, 3 and 4 show detailed enlarged sectional views of the heat sealing filter sheet material at successive progressive steps during the manufacture thereof using a filtering sheet material formed of a vegetable fibrous pulp as a base layer, taken at lines 2-2, 33 and 4-4 in Fig. 1;

Figs. 2a, 3a and 4a show detailed enlarged sectional views of the heat sealing filter sheet material showing successive progressive similar steps to Figs. 2, 3 and 4, using a filter sheet material formed of cotton staple pulp as a base layer;

Figs. 2b, 3b and 412 show detailed enlarged sectional views of the heat sealing filter sheet material showing successive progressive steps similar to Figs. 2, 3 and 4, using a filtering sheet material formed of perforated parchment paper or Cellophane sheet, as a base layer;

Figs. 2c, 30 and 40 show detailed enlarged sectional views of the heat sealing filter sheet ma terial showing successive progressive steps similar to Figs. 2, 3 and 4 using a cotton gauze textile sheet material, as a base layer;

Figs. 5 and 6 are front and side elevational views, respectively of a complete tea-ball with string handle and tag constructed to embody'the invention;

Fig. 7 is a cross-sectional view taken on line 1-1 in Fig. 5;

Fig. 8 is a front elevational view of a fragmentary portion of a tea-ball showing a modified construction of the heat sealed seam joints and anchorage for the string handle; and

Fig. 9 is a cross-sectional view taken on line 99 in Fig. 8.

In practising the embodiment of the invention for manufacturing tea or coffee balls l0 and particularly heat sealing filter sheet material H for constructing the container or bags lOa thereof, a suitable filter paper sheet in the form of base layer I I a, such as made from a vegetable fibrous pulp stock may be used. Said filter paper layer Ila is such that when made into the container or bag Illa of the tea or coffee ball I0 preferably has sufficient strength to retain the shape and form of the tea-ball l0 on immersion in boiling water without damage or disintegration. The filter paper layer II a of the container Illa portion of the-ball I0 serves to permit ready infusion, that is, passage therethrough of the water of immersion for forming a brew and to strain the filling or contents T, such as tea, or coffee from passing out of the ball Ill, said layer Ila being of such composition that it is insoluble non-toxic Y facturing bag Illa and does not impart in the slightest degree any odor or taste to the brew and has no chemical reaction therewith.

Referring now to Fig. 1, the process of manufacturing the improved heat sealing filter sheet II is seen to consist in thinly spreading a finely divided plastic I2 over one side llb of successive surface portions of filter paper sheet base layer Ila passing under suitable spraying means 5,- sald base layer Ila being preferably in the form of a moving web or strip, a section thereof being shown in Fig. 2. The plastic used may be a synthetic resin of the phenol, urea, formaldehyde, glycerol, phthalic anhydride, acetylene, rubber and petroleum group, and provides the heat sealing means in the manner hereinafter described. The specific group of synthetic resin here selected to produce heat sealing filter sheet ll illustrating an embodiment of the invention is a thermosetting polymerizing resinous product such as powdered or finely granulated copolymer of vinyl chloride and vinyl acetate, which will leave the heat sealing filter sheet ll after being processed with no part thereof that will dissolve, give off any odor, alter the taste, or otherwise impart toxic or injurious effects as a food product when incorporated in the finished tea or coffee ball Ill and immersed in boiling water for brewins.

The base layer Ila spread with said plastic I2 over one surface lIb thereof is next heated by any suitable means, such as heater H, to a degree sumcient only to cause the plastic I2 to flow, that is, to soften and cohere, and in which state it is pressed between suitable rollers R or the like to form a film, lamina or superficial coating Ila of finely divided inorganic material adhering to said side I lb of .the base layer Ila, as shown in Fig. 4. The degree of heat applied to said plastic I2, however, is insufiicient to cause a permanent setting of the plastic forming coating I2a. When said coating l2a is a copolymer of vinyl chloride and vinyl acetate heating temperature of approximately 65 C. will be found satisfactory. Because the base layer lla used is formed of a vegetable fibre pulp, the rolled coating I20. adheres and is retained by an adsorption thereof around and about the pulp fibres as a pervious structure without substantially decreasing the original porosity or practically effecting the filtering capacity of the paper base layer Ila.

After base layer Ila with the lamina or rolled coating .I2a is cooled to room temperature it hardens, which will hereinafter be referred to as partial fusion or partially fused." In this state said coating I2a forms with the base layer Ila heat sealing sheet material II which remains flexible and may be coiled up in rolls (not shown) in the well understood manner, ready for use in making containers or bags Illa for ball Ill. Heat sealing sheet material II when used for the last named purpose is cut into proper size for manuwhich when filled with the contents T, such as tea or coifee, and closed forms the ball III. The containers or bags Illa are each constructed with the coating I2a side of the sheet material II as the interior surface thereof. The edge joints or seams Illb and top closure seam IIIc are made by having the coating I2a portion thereof placed in face to face relation, pressed together and heated to a fusion temperature by suitable clamp means of any well known construction to unite the parts forming said edge joint seams Iflb or closure seam IIIc in as a pervious of copolymer of vinyl chloride and vinyl acetate such permanent sealing fusion will take place when pressed and heated to about 130 C.

Referring now to Figs. 5 to 'I, where it is desired to provide a string handle I3 of cotton strands terminated by a tag Il, the strands of the string handle Ila preferably may be processed with a plastic I2 to a partially fused" state in the manner above in the manufacture of heat sealing sheet material I I. An end Ila of the string handle I3 may be inserted between the coated side face to face portions I2a of said sheet material I I during the formation of the top closure joint or seams I00, and the final sealing heat applied simultaneously to anchored end l3a within the joint seams Illc and the entire joint seam Illc for permanently fusing thereof.

To secure the tag ll to the terminating or free end lib of the string handle l3 opposite the anchored end I3a, one side Ila of each tag Il may also be processed in the manner described above in the manufacture of heat sealing sheet material II, and if desired may be folded over said processed string handle end I3b therebetween. The partially fused plastic material side Ila of said tag ll in face to face relation and the string handle end I3b are then united on pressure and application of heat to a degree for permanent fusion.

While the above described method of attaching the tag ll to the string handle end lib is preferred, it is to be understood that such attachment may also be accomplished by simply pressing and permanently fusing the string handle end Ilb to the coated Ila side of the tag ll without folding of the latter.

In Figs. 2a, 3a and 4a there is illustrated the results of successive steps of the improved manufacturing process applied to a filter paper base layer Illa formed of cotton staple pulp stock having an upper surface Illb on which the said plastic I2 is thinly spread, and which when heated, roller and cooled for "partial fusion" provides a lamina or superficial coating III: as part of heat sealing filter sheet material I in the same manner as described above for the heat sealing filter sheet material I I. The coating I2a formed on the side Illa coheres and is retained by an absorption thereof on the portion of the side lb of cotton staple pulp of base layer Illa structure without substantially decreasing the original porosity of said filter paper base layer Illa.

Although filter paper base layer Illa formed of cotton staple pulp stock has a much lower tensile strength when wet and immersed in hot water than filter paper base layer Ila of the same thickness formed of vegetable fibre pulp stock,

. which otherwise the addition of the superficial coating In on either of said layers Ila or Illa increases the wet tensile strength of each, and in the case of base layer Illa makes the same of sufllcient strength to be practical for making all types of tea balls III would not be possible. A thinner grade of filter sheet layer Ila or Illa can also be used than would otherwise be required in making bag Ila if the superficial coating I2a was not provided.

Since the structures of the filter sheet base layers Ila and Illa are made of paper pulp stock, when each is provided with a porous lamina l2a the thermosetting heat sealing filter sheet materials II and Ill, respectively, formed, are inpermanent adhesion. With coatings I2a formed herently sift-proof when usedfor making infusion similar to that described asoasoo 3 bags containing even the finest of powdered prodtensile strength of the string handle It is mateucts, such as tea T having dry dust particles as rially increased, thereby permitting the use of part of the contents thereof. thinner cotton strands forming said string handle In Figs. 2b, 2c and 2d there is shown successive for saving such strand material. steps of the improved manufacturing process ap- It .will thus be seen that there is provided a plied to a filter base layer 2||a formed of a package, package making material anda method parchmentlzed paper, cellophane or the like base for producing the latter in which the several oblayer, perforated at 2| lo and having an upper .Iects of the invention are achieved and which are surface 2||b on which a superficial coating or well adapted to meet the conditions of practical lamina |2a is formed from spread partially use. fused" plastic i2 embodying the invention to pro- As various other possible embodiments of the vide heat sealing filter sheet material 2| I, the invention might be made of the above invention, parchmentized paper base layer 2| |a being of the and as various changes might be made in the type used for cooking purposes. If clogging up embodiments above set forth, it is to be underthe perforation 2| I0 is experienced when providstood that all matters herein set forth or shown ing the coating I20, an additional step (not in the accompanying drawings and described in shown) of blowing air upwardly through the layer the specification is to be interpreted as illustrative 2| la to clear the perforation 2| ie before partial and not in a limiting sense. fusion said coating |2a is completed. I Having thus described my invention, I claim as Instead of using as base layers Ila, la and 0 new and desire to secure by letters Patent:

2||a described above, a filter cotton gauze or woven textile base layer 3| I a may be substituted surfaces of the cotton strands of the side 3| lb having an upper surface 3| lb on which the finely divided plastic I2 is thinly spread and which when processed to provide the superficial coating or lamina |2a forms a heat sealing filter sheet 3| I which may be used like heat sealing filter sheet material again the superficial coating I M is retained by an absorption thereof on portions of the upper surfaces of the cotton starands of the side 3||b forming the gauze layer 3| Ia as a pervious structure without substantially decreasing the original porosity of said filter cotton gauze base layer 3| la.

The superficial coating |2a also serves to increase the tensile strength of heat sealing filter sheet material 2 and 3 so that the base layer materials 2| la and 3| I a, respectively, may be thinner than is practically required when such coating lZa is not used.

Each of the heat sealing filter sheet materials Ill, 2 and 3 remain flexible and may be coiled up like sheet material described above, and any one of said sheet materials II, ill, 2 or 3| I may be utilized for forming the bags Illa by providing permanently fused joint seams in the entire construction or in part thereof and for making complete tea ball ||l with string handles it and tags It in the same manner as described above.

If desired the fused edge portions may be impressed or embossed by suitable die (not shown) with word, legend or symbol IS on application of molding pressure dur' g the permanent fusing of the seam joint lob, see Fig. 5.

In Figs. 8 and 9 there is shown another construction of tea ball seam joints and anchorage for the string handle. Here the closure seam joint 00 and edge seam joint ||0b are made with a fold which preferably is formed prior to the permanent fusing thereof. The resulting seam will be found to be a united s'tiifened structure. The string handle end |3a is also located within the fold as shown, prior to the permanent fusion operation. In providing this folded type of stiffened seam joint structure along the edge portions of the tea balls, the same serves as a shape retaining means.

It should be noted that by coating the cotton strands of the entire string handle |3 with a partially fused thermosetting plastic I2 and finally fusing same, as for example, simultaneously with the formation of joint seam liic or the attach- Ill and 2 described above. Here the remaining interior surfaces ment of the tag ll with-the string handle l3, the

portion forming a l. A package containing an infusion product, a pervious bag free from perforations enclosing said product and formed of a single heat sealing sift proof filter sheet, the latter comprising a filter sheet layer base coated on one side thereof with a dry porous lamina of partially fuseo" thermosetting plastic to form the interior surface of said bag, said bag having a joint seam united by a face to face permanent fusion of said lamina along said joint seam to form an edge closure for the bag, said filter layer and lamina coating of constructed and arranged to have a filtering capacity substantially that of said layer alone.

2. The package defined in claim 1 in which said edge closure is of substantially uniform cross-sectional shape throughout the length thereof, and outer surface of the edge closure having impressed therein an indicia.

3. The package defined in claim 1 having a string handle terminated by a tag at a free end thereof, the other end of said string handle being coated with a partially fused thermosetting plastic, said last mentioned end being anchored r in said joint seam by the permanent fusion in the edge closure.

4. The package defined in claim 1 having a string handle terminated by a tag at a free end thereof, the other end of said string handle being coated with a partially fused thermosetting plastic, said end being anchored in the joint seam by the permanent fusion in the edge closure, the

free end of said string handle and a surface portion of the tag also being coated with a partially fused thermosetting r' ..stic for securing the tag to said free string handle end by a permanent fusion of the plastic coatings of said free string handle end to said tag surface portion.

5. A package containing an infusion product, a pervious bag enclosing said product and formed of a heat sealing sift-proof filter sheet, the latter comprising a filter sheet layer base coated on one side thereof with a dry porous lamina of partially fused" thermosetting plastic to form the interior surface of said bag, said bag having a folded edge joint seam, the latter being permanently united in folded condition by a final fusion of said lamina thereof.

6. A package containing an infusion product, a pervious bag enclosing said product and formed of a heat sealing filter sheet, the latter comprising a filter sheet layer base coated on one side there of with a dry porous lamina of partially fused thermosetting plastic to form the interior surface of said bag, said bag having a folded edge porcoated with a partially fused thermosetting.

plastic and anchored in the folded closure joint seam by said final fusion.

'7. A package of the character described having an infusion product, a container enclosing said product formed of imperforated strainer sheet material adapted to permit water to permeate therethrough, said strainer sheet material comprising a foraminous layer coated with a dry filter film of a partially fused" thermosetting plastic on one-side of the layer so constructed and arranged that said layer and the filter film have substantially the same filtering capacity as said foraminous layer without the filter film, the latter having heat sealing properties for making joint seam portions ofthe container when such portions are placed in face to face relation and heated to a degree for causing a final fusion of film coating, said bag having said partially fused plastic and permanent adhesion of said portions.

8. In a package of the character described containing a product for making an infusion, a bag formed of sift-proof filter sheet material adapted to strain any finely powdered portion of said product from an infusion thereof permeating through the bag, said sheet material comprising an imperforated porous base layer coated with a dry film of a partially fused plastic having thermosetting properties and spread on one'side of said layer as an imperforated porous lamina, said filter sheet having substantially the same filtering capacity as the base layer without the I joint seams formed by "partially fused portion thereof placed in face to face relation and thermosettingly fused to a permanent adhesion of said portion.

9. In the package as defined in claim 8 the joint seams being formed with folded edge portions which are permanently united in folded condition by said permanent adhesion thereof.

- THEODORE F. 'MENZEL. 

